The present invention relates to a vibration or jarring table which essentially comprises a stationary base and a table top for absorbing loads which can be periodically moved back and forth and is hydrostatically or pneumatically supported on the base.
With such vibration tables, the table tops are operatively connected with vibration exciters or oscillators, and can, for example for workpieces which are to be tested, be linearly moved, with moments and possibly also transverse forces which occur thereby being absorbed by the table top. In this connection, it is customary to use hydrostatic or pneumatic supports which have a plurality of individual adjustable support positions, and upon which the table top can be supported in such a way as to be slidingly movable; alternatively, the table top can be allowed to float freely on a lubricating film located between the bearing surfaces.
Vibration tables of the aforementioned general type are disclosed in catalog 481 of Kimball Industries Incorporated, Monrovia, Calif. Hydrostatic supports disposed, for example, in the region of the corners of the table top serve to support the latter. With this arrangement of the supports at only a few points of the table top, the table top, with the test body located thereon, frequently executes tilting movements at right angles to the load direction as a result of the natural bending frequencies of the table top.
Simpler vibration tables are also known, according to which the table top is placed upon a plate which generally comprises granite. With these vibration tables, when tilting moments occur the table top is lifted from the base and executes uncontrollable wobbling movements. Therefore, table tops which rest upon granite are often additionally equipped with a plurality of hydrostatic supports.
The drawbacks to the heretofore known embodiments of vibration tables are the great expense, the limited ability to absorb moments and transverse forces, as well as the unfavorable tilting conditions and the large mass of the table top and supports.
It is an object of the present invention to provide a vibration table of the aforementioned general type which is distinguished by a simple construction which avoids the heretofore known drawbacks, and by a reliable operation.